Web developers using high amounts of domain sharding to work around low connection per host limits in old browser should reconsider their number of shards for newer browsers. Anything over 2 is probably too much, unless most of your user base is using older browsers.

At Bugsnag we use SPDY on our production rails application. For our users who run modern browsers, this can make the site feel much faster and more responsive. Want to get SPDY working on your production rails app? Read on. What is SPDY?

SPDY is awesome. It's the first real upgrade to HTTP in 10+ years, it tackles high latency mobile networks performance issues and it makes the web more secure. SPDY is different than HTTP in many ways, but its primary value comes from being able to multiplex many requests/responses from client to server over a single (or few) TCP connections.

SPDY is a replacement for HTTP, designed to speed up transfers of web pages by eliminating much of the overhead associated with HTTP. SPDY supports several optimizations that give it an edge over HTTP when it comes to speed.